I've noticed a considerable pause when going backwards through the book using the Previous button. The actual page change is fast but there is a delay before it starts the process. Nothing happens for a sec, and then it changes.

It only happens when clicking on pages that haven't been viewed during the reading session.

ie. Enter book.. Click forwards through five pages, and then back five pages, it'll all be fast. However, click a sixth page back and there's a delay before it displays.

Likewise entering a book and immediately clicking back also causes the pause.

This is common to all version of Mobipocket Reader. Going backwards through a book is always slower than going forwards. Just the way it is. As you note, it appears to be related to the way that pages are cached.

Mine acts a little differently. If I back-page, the first three screen changes will be fast, then slow after that. Happens even if I go forward five pages (screens, whatever), then back again.

Not that big a deal since I don't usually have to back up very often. But sometimes I wish it had the ability to go back or forwards say, five or ten pages, if you held down the page-turn button for a couple of seconds. My old Astak reader would do that. Came in handy some times.

haha DiapDealer, I like to flick back a page or two when picking up a book to jog my memory!

harry - you've put my mind at rest a little as it did seem like a caching issue. I couldn't remember it happening on my Kindle firmware 3.0.1, so wondered if they'd reduced the cache to speed up other processes, such as menus.

mrsquash - sounds worse than mine! It's odd how results vary between Kindles, not sure I like that! Wish I hadn't updated it.. but I got very slow page turns earlier when it was out in the cold.